Summer Strawberry Salad

Preheat oven to 350 degrees F (175 degrees C). Spread walnuts on a baking sheet.

Toast in preheated oven until walnuts start to turn golden brown and become fragrant, 5 to 7 minutes. Let cool, about 5 minutes.

Toss toasted walnuts, strawberries, iceberg salad, baby spinach, feta cheese, red onion, and black pepper together in a large bowl.